package com.tjf.record;

import android.media.AudioFormat;
import android.media.AudioRecord;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class PcmToWavUtil {
    private int mBufferSize; // 缓存的音频大小
    private int mSampleRate = 16000; // 此处的值必须与录音时的采样率一致
    private int mChannel = AudioFormat.CHANNEL_IN_MONO; // 单声道
    private int mEncoding = AudioFormat.ENCODING_PCM_16BIT;

    private static class SingleHolder {
        static PcmToWavUtil mInstance = new PcmToWavUtil();
    }

    public static PcmToWavUtil getInstance() {
        return SingleHolder.mInstance;
    }

    public PcmToWavUtil() {
        this.mBufferSize = AudioRecord.getMinBufferSize(mSampleRate, mChannel, mEncoding);
    }

    /**
     * @param sampleRate sample rate、采样率
     * @param channel    channel、声道
     * @param encoding   Audio data format、音频格式
     */
    public PcmToWavUtil(int sampleRate, int channel, int encoding) {
        this.mSampleRate = sampleRate;
        this.mChannel = channel;
        this.mEncoding = encoding;
        this.mBufferSize = AudioRecord.getMinBufferSize(mSampleRate, mChannel, mEncoding);
    }

    /**
     * pcm文件转wav文件
     *
     * @param inFilename  源文件路径
     * @param outFilename 目标文件路径
     * @param deleteOrg   是否删除源文件
     * @param onSuccess   成功回调
     * @param onFailure   失败回调
     */
    public void pcmToWav(String inFilename, String outFilename, boolean deleteOrg,
                         OnSuccessCallback onSuccess, OnFailureCallback onFailure) {
        try (FileInputStream in = new FileInputStream(inFilename);
             FileOutputStream out = new FileOutputStream(outFilename)) {

            byte[] data = new byte[mBufferSize];
            ByteArrayOutputStream buffer = new ByteArrayOutputStream();

            // Read all data into buffer
            int bytesRead;
            while ((bytesRead = in.read(data)) != -1) {
                buffer.write(data, 0, bytesRead);
            }
            byte[] audioData = buffer.toByteArray();
            long totalAudioLen = audioData.length;
            long totalDataLen = totalAudioLen + 36;

            int channels = mChannel == AudioFormat.CHANNEL_IN_MONO ? 1 : 2;
            long byteRate = mSampleRate * channels * (16 / 8);
            int blockAlign = channels * (16 / 8);

            writeWaveFileHeader(out, totalAudioLen, totalDataLen, mSampleRate, channels, byteRate, blockAlign);
            out.write(audioData);

            if (deleteOrg) {
                new File(inFilename).delete();
            }

            if (onSuccess != null) {
                onSuccess.onSuccess(outFilename);
            }
        } catch (IOException e) {
            if (onFailure != null) {
                onFailure.onFailure(e);
            } else {
                e.printStackTrace();
            }
        }
    }

    public void pcmToWav(String inFilename, String outFilename) {
        pcmToWav(inFilename, outFilename, false, null, null);
    }

    /**
     * 加入wav文件头
     */
    private void writeWaveFileHeader(FileOutputStream out, long totalAudioLen,
                                     long totalDataLen, long longSampleRate, int channels, long byteRate, int blockAlign)
            throws IOException {
        byte[] header = new byte[44];

        // RIFF/WAVE header
        header[0] = 'R';
        header[1] = 'I';
        header[2] = 'F';
        header[3] = 'F';
        header[4] = (byte) (totalDataLen & 0xff);
        header[5] = (byte) ((totalDataLen >> 8) & 0xff);
        header[6] = (byte) ((totalDataLen >> 16) & 0xff);
        header[7] = (byte) ((totalDataLen >> 24) & 0xff);
        header[8] = 'W'; // WAVE
        header[9] = 'A';
        header[10] = 'V';
        header[11] = 'E';
        header[12] = 'f'; // 'fmt ' chunk
        header[13] = 'm';
        header[14] = 't';
        header[15] = ' ';
        header[16] = 16; // 4 bytes: size of 'fmt ' chunk
        header[17] = 0;
        header[18] = 0;
        header[19] = 0;
        header[20] = 1; // format = 1
        header[21] = 0;
        header[22] = (byte) channels;
        header[23] = 0;
        header[24] = (byte) (longSampleRate & 0xff);
        header[25] = (byte) ((longSampleRate >> 8) & 0xff);
        header[26] = (byte) ((longSampleRate >> 16) & 0xff);
        header[27] = (byte) ((longSampleRate >> 24) & 0xff);
        header[28] = (byte) (byteRate & 0xff);
        header[29] = (byte) ((byteRate >> 8) & 0xff);
        header[30] = (byte) ((byteRate >> 16) & 0xff);
        header[31] = (byte) ((byteRate >> 24) & 0xff);
        header[32] = (byte) (blockAlign & 0xff);
        header[33] = (byte) ((blockAlign >> 8) & 0xff);
        header[34] = 16; // bits per sample
        header[35] = 0;
        header[36] = 'd'; // data
        header[37] = 'a';
        header[38] = 't';
        header[39] = 'a';
        header[40] = (byte) (totalAudioLen & 0xff);
        header[41] = (byte) ((totalAudioLen >> 8) & 0xff);
        header[42] = (byte) ((totalAudioLen >> 16) & 0xff);
        header[43] = (byte) ((totalAudioLen >> 24) & 0xff);

        out.write(header, 0, 44);
    }

    public interface OnSuccessCallback {
        void onSuccess(String filePath);
    }

    public interface OnFailureCallback {
        void onFailure(Exception err);
    }
}
